光流法在台风路径预报检验与订正中的应用

Application of Optical Flow Method to Verification and Correction of Typhoon Track Forecast

本文在台风路径预报检验与订正方面引入了光流法,结果表明:(1)利用光流检验方法,可以将位势高度场的预报误差分解为强度、位移和角度3种误差场,实现整个误差场的量化。利用位移和角度误差场即可进行台风路径预报的检验和订正。(2)从“莫兰蒂”台风过程可以看到,对相同的过程,不同数值模式一般表现不同。对一次台风过程可以连续跟踪不同数值模式的预报偏差,从中发现预报稳定性最好的模式,再利用这个模式的位移和角度误差进行台风路径预报的订正,这也是提高台风路径准确度的一个有效途径。

This paper introduces the application of the optical flow method to the verification and correction of typhoon track forecast.The results show that:(1)By using the optical flow verification method,the prediction error of the geopotential height field can be decomposed into three error fields:intensity,displacement,and angle,and the quantization of the whole error field can be realized.The verification and correction of typhoon track forecast can be carried out by using the displacement and angle error fields.(2)As can be seen from the process of Typhoon Meranti,different numerical models,for the same process,generally behave differently.In the same typhoon process,the forecast deviation of different numerical models can be continuously tracked,and the model with the best forecast stability can be found.Then the displacement and angle errors of this model can be used for typhoon track forecast correction,which is also an effective way to improve the typhoon track forecast accuracy.